


Flex

by avoidingavoidance



Category: Haikyuu!!
Genre: Aged-Up Character(s), M/M, Plot What Plot/Porn Without Plot
Language: English
Status: Completed
Published: 2016-06-10
Updated: 2016-06-10
Packaged: 2018-07-14 06:07:06
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 691
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/7156616
Author URL: https://archiveofourown.org/users/avoidingavoidance/pseuds/avoidingavoidance
Summary: <blockquote class="userstuff">
              <p>Oikawa is the king of asking for weird things during sex, and this time is no different.</p>
            </blockquote>





	Flex

**Author's Note:**

> listen....... i saw a video of a dude doing situps mid-sex and my brain was like "iwaoi" and i just. ;;;;;;;;;;;;; don't look at me

Oikawa is notoriously full of _horrible_ ideas. It’s basically his legacy at this point.

Iwaizumi would be tempted to think that this is one of them, but it’s kind of hard for him to argue with anything Oikawa asks of him when he’s sitting so nicely in his lap, taking Iwaizumi’s cock so perfectly. 

“Please, Iwa-chan?” Oikawa all but _purrs,_ his hands tracing down Iwaizumi’s chest, dragging his knuckles reverently up the defined muscles of his abdomen. “I’ll never ask you for anything weird again.”

“That’s a lie,” Iwaizumi immediately retorts.

“How mean,” Oikawa pouts, but he can’t exactly refute it. 

In an effort to save some face, Iwaizumi rolls his eyes and huffs a put-upon sigh, but the way Oikawa’s still languidly riding him takes most of the edge off his irritation. He still aims a judgmental frown up at him, though; god forbid Oikawa ever find out just how easy it is to get Iwaizumi to play into his strange little sex games.

“I can’t believe you want me to do sit-ups while you’re sitting on my dick,” he grumbles, wishing he was even a little bit put off by the idea. Oikawa tightens around him, though, and breathes this sweet little moan as his long eyelashes flutter, and Iwaizumi’s utterly helpless.

Lacing his fingers behind his head, Iwaizumi gives Oikawa one last flushed, disgruntled look before flexing his abs and curling up off the sheets, and any lingering embarrassment he might be feeling goes flying right out the window at the sheer _hunger_ in Oikawa’s dark gaze.

The thin walls in their college dorm aren’t made for the kinds of noises Oikawa’s making. He’s staring down at Iwaizumi's stomach as he obliges him, flexing and tensing, slick with their shared sweat, and even when Oikawa braces his hands on Iwaizumi’s thighs and leans his weight there, Iwaizumi can’t quite manage a full sit-up. That might have something to do with the fact that Oikawa’s mostly using the support to honest-to-god _bounce_ himself on Iwaizumi’s cock, wanton moans slipping freely between his flushed lips, fueled further by his boyfriend’s willingness to bend to his odd cravings.

It doesn’t take much more to send Oikawa over the edge. The way Iwaizumi’s staring up at him, arching up toward him, both of them panting for breath, how _good_ the angle is for both of them—Oikawa’s gasping and whining and crying out for Iwaizumi long before he’s even close to getting sore from the sit-ups, his clever tongue tripping over Iwaizumi’s given name as he spills all over his stomach, his chest, leaving white-hot streaks across the body he’s so fond of worshiping.

As he sits heavily in Iwaizumi’s lap and shivers his way through his orgasm, Iwaizumi groans and moves his hands to Oikawa’s hips, holding him still so he can fuck up into him for the few thrusts it takes before he’s overcome too. The rush of his orgasm has him arching off the sheets again, Oikawa’s name slipping out between his gritted teeth with every huffed breath, until he buries himself deep and collapses again, eyes blissfully closed.

Oikawa slumps forward onto him shortly after, panting against his cheek and smearing his come between them. Iwaizumi grumbles, but slings one arm around Oikawa’s waist, tugging him closer so he can bury his face in soft, mussed hair. 

He’s given about thirty seconds of peace before Oikawa’s weird brain comes back online. He reaches over to Iwaizumi’s other arm and drags his palm along his bicep with a content sigh, impressed as always with the definition of his boyfriend’s muscles. “My big buff Iwa-chan,” Oikawa sighs happily. He lets Iwaizumi hide for a moment longer before he leans up over him and plants a loud, obnoxious kiss on his lips, then chirps, “Happy birthday.”

Iwaizumi wrinkles his nose at that. “Seems more like your present than mine.”

“And here I thought you loved making me happy,” Oikawa laughs, his grin widening.

Rolling his eyes loudly, Iwaizumi drags Oikawa back down onto his chest so he doesn’t have to dignify that with a response.

Besides, they both know it’s true.

**Author's Note:**

> i have a [tumblr](http://avoidingavoidance.tumblr.com)


End file.
